Description

http://framework.zend.com/manual/en/… describes passing a $conditionalHttpEquiv parameter as a modifier to methods such as appendHttpEquiv.
Although there are no code examples for what to pass for headMeta, there are examples in headScript which pass an array of the form ('conditional' => 'lt IE 7'), for example.

Zend_View_Helper_HeadMeta::itemToString() does nothing with a conditional key, whereas Zend_View_Helper_HeadScript::itemToString() treats 'conditional' as a special case and wraps the value in a javascript comment.